* {
    margin: 0;
    padding: 0;
}

.nav_bottom {
    width: 100%;
    height: 1.3333rem;
    background: #ffffff;
    display: flex;
    position: fixed;
    bottom: 0;
    justify-content: space-around;
    border-top: 1px solid #ccc;
    z-index: 1;
}

a {
    width: 20%;
    height: 100%;
    color: #666666;
    text-decoration: none;
    display: block;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-size: .32rem;
}

a div {
    width: .64rem;
    height: .64rem;

}

a:nth-child(1) div {
    background: url("./img/home.png") no-repeat;
    background-size: 100%;
}

a:nth-child(2) div {
    background: url("./img/type.png") no-repeat;
    background-size: 100%;
}

a:nth-child(3) div {
    background: url("./img/ceo.png") no-repeat;
    background-size: 100%;
}

a:nth-child(4) div {
    background: url("./img/cart.png") no-repeat;
    background-size: 100%;
}

a:nth-child(5) div {
    background: url("./img/mine.png") no-repeat;
    background-size: 100%;
}

a.active {
    color: red;
}

a:nth-child(1).active div {
    background: url("./img/home-hl.png") no-repeat;
    background-size: 100%;
}

a:nth-child(2).active div {
    background: url("./img/type-hl.png") no-repeat;
    background-size: 100%;
}

a:nth-child(3).active div {
    background: url("./img/ceo-hl.png") no-repeat;
    background-size: 100%;
}

a:nth-child(4).active div {
    background: url("./img/cart-hl.png") no-repeat;
    background-size: 100%;
}

a:nth-child(5).active div {
    background: url("./img/mine-hl.png") no-repeat;
    background-size: 100%;
}